Fainting: Causes and effects - FOX 18 - Quad Cities News and Weather

By Louis Neipris, M.D., Staff Writer, myOptumHealth
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Fainting is a brief loss of consciousness caused by decreased blood flow to the brain. When people faint, they often slump to the ground. In a lying down position, more blood can flow to the brain and recovery usually occurs.

Any loss of consciousness - other than when you fall asleep - is a reason to see the doctor.

And some circumstances, such as when you pass out for more than one minute, require emergency care.

Just over a third of people faint at some point in their lives. While fainting is usually not a sign of a serious medical condition, report any fainting spells to your doctor right away.

Also, note any other symptoms that occur when you faint and report them, too. For example, if you have heart palpitations, headache or dizziness just before fainting. These signs could help doctors pinpoint the underlying cause.

So once you're back on your feet, don't forget your fainting episode. Remember your symptoms and call your doctor right away for an accurate diagnosis and proper care.

What causes fainting?
The two common causes of fainting are the vasovagal reflex and orthostatic hypotension.
Vasovagal reflex. This is the most common cause and usually isn't serious. Your body overreacts to certain events, like seeing blood, standing in hot crowded areas or extreme pain. This reflex causes blood to pool in the lower body, decreasing blood flow to the brain and causing fainting.

Symptoms may include:

• Feeling dizzy
• Feeling weak in the knees
• Sweating
• Paleness
• Nausea
• Yawning
• Fast breathing
• Blurred vision or color changes in vision
• Buzzing/ringing in the ears
• Heart palpitations (even if the problem is not heart-related)

Orthostatic hypotension. Sometimes when you stand or change position too quickly, you get a sudden drop in blood pressure, which may cause you to faint. Dehydration, old age, certain medications and other factors can make this type of fainting more likely.

Other causes of fainting
The other causes of fainting may be more serious but are not as common. They include:

• A heart problem. This might include an irregular fast or slow rhythm, a narrow valve or thickened heart muscle. Fainting due to a heart problem tends to happen a lot faster than vasovagal syncope. There may be no warning signs. Pounding or a fluttering feeling in your chest could be caused by an irregular heart rhythm. Some people feel just a thud in the chest.
• A neurological problem. Fainting may be caused by a neurological problem, such as epilepsy (seizure disorder) or stroke.
• Metabolic or hormone-related causes. These include low blood sugar or lack of oxygen.

What to do about fainting

1. Take action. When you notice symptoms, get off your feet right away before passing out. Tell someone around you that you are feeling faint.
2. After fainting. Make sure any other symptoms go away completely. Stay off your feet for a few minutes. Lie down with your feet slightly elevated (6 to 8 inches) to promote circulation. Loosen any tight clothing.
3. Call 9-1-1 if you faint or feel faint and have any of the following:
   • Loss of consciousness for more than one minute
   • Trouble breathing
   • Chest pain, pressure, tightness or heaviness; nausea and vomiting or feeling your heart fluttering, racing or beating very slowly
   • Sudden severe headache; trouble walking or talking; weakness or numbness in the face, arm or leg; confusion; blurred vision or vision loss
   • A pacemaker or implantable cardiac defibrillator
   • A seizure

Treatment in the emergency room is needed if you pass out:

• And have head trauma
• And are elderly, very ill or have chronic medical problems
• During or immediately after exercise
• More than once

1. For fainting caused by low blood sugar related to diabetes medications, tell the people you spend time with about the possibility of a hypoglycemic or low blood sugar reaction. Instruct them on what to do and to call 9-1-1 if you faint.
2. Try preventive measures:
   • If you have a tendency to faint, avoid situations that make you pass out.
   • If you faint during or following shots, tell your doctor in advance. Make sure you are sitting or lying down. Drink fluids beforehand.

Call your doctor if you faint
Any case of fainting should be checked out, even if you feel fine afterward. During the visit, give your doctor the details about the fainting episode. Explain what you were doing at the time, and about any other symptoms you had. Tell your doctor about all of your medications.

Your doctor may need to do tests to evaluate your heart rate and function and may also need to do some blood work. Your doctor may also:

• Check how your body responds to position changes with a "tilt table" test
• Do neurological imaging, such as a CT scan or brain MRI

SOURCES:

• Parmet S. Fainting. Journal of the American Medical Association. 2004; 292 (10): 1260

• Centers for Disease Control and Prevention. Syncope FAQs. Vaccine safety. Accessed: 05/21/2010

• Heart Rhythm Society. Neurocardiogenic and non-cardiovascular syncope Accessed: 05/19/2010

• Kuriachan V,Sheldon RS, Platonov M. Evidence-based treatment for vasovagal syncope. Heart Rhythm. 2008; 5 (11): 1609-1614

• Shukla GJ, Zimetbaum PJ. Syncope. Circulation.2006; 113:e715-e717.

• Wieling W, Thijs RD, van Dijk N, Wilde AA, Benditt DG, van Dijk JG. Symptoms and signs of syncope: a review of the link between physiology and clinical clues. Brain. 2009 132(Pt 10):2630-42